Commutator-brush



(No Model.) A

F. MGLAUGHLIN.

GQMMU'TATOB BRUSH.

* No. 432,206. Patented July 15, 1890.

. UNITED ,STATESV PATENT' OFFICE;

JAMES F. li'lCLAUGlllilN, OF PHILADELPHIA, PENNSYLVANIA.

eo M M UTATOR- B Rosi-1 SPECIFICATION forming pai-t of Letters PatentNo, 432,206, dated .my l15, 1890- Application filed March 19, 1890.

certain new and useful Improvements in Commutatorjllrushes, -of whichthe following is 'a specification. l

My invention has reference to improvements Yin collector-brushes fordynamo-electric generators and motors, the object being to render carbonbrushes, which are now gem orally employed in dynamo-electric machines,

more durable withoutimpairing the general utility of suel1-b1uslies. y

It has been` found that if the collectorbrushes for dynamo-electricmachines are made of' carbon the sparking heretofore 0bservedwhenmetallic brushes were usedl is almost entirely avoided, owing to theperfect eontaet which a body oficarbon is capable of making with amoving surface. Collector,- brushcs of this character, however, havethis disadvantage, that by reason of the lack of .homogeneity of thecarbon and by reason of the brittleness of the same t-he edges of thecontact-surfaces are frequently broken away, whereby the extent ofcontact-surface is reduced and the brush is consumed much more rapidlythan would otherwise be the case. It also frequently occurs that acarbon. brush breaks away altogether betweenl its contactfa-ce and thebrush-holder, and frequent renewals of new collector-brushes aretherefore necessary. To obviate in a measure this lastmeutioned defect,it has been found necessary to reduce the distance between thebrushholder and the face of the eommutator to a minimum, for the longerthe collector-brush is the greater is the liability of its being brokenifmade of such brittle substance as carbon. lily my improvement lovercome all these objections in a Very simple manner, as will appear.from the following detailed deseiiptioinin which reference is made tothe accompanying drawings, which form a part thereof, and in whichFigure l represents a perspective view of the eommutator of adynamo-electric machine provided with a collector-brush of my iin--proved construction. Fi v view of my improved collector-brush with theis a sectional` sereinement. uit muret) brush-holder and adjustingdevices for the same, the sect-ion being' taken on line u: zu, Fig. 1.

Fig. 3'is an end view ol' the brnsh-55 holder with a pivoted framesupporting the l feeding mechanismswung open; and Fig. 'is asect-ionalviewon the 1ine`y/ //,-l `ig. 3,with

the feeding' mechanism in position.`

Likek numerals-of .reference indicato like 6o parts all throughout the dawingL of 4any ordinary or 'improved 'construetion,

has, as shown in the drawings, pivoted con centriewith its avis an arm2, which has seL cured at its free enda su pporting-rod 3, e.\` tendingparallel with the axis of the commutatOr-cylinder, and upon which is adjust'ably Secured the brush-holder fr. lt will be understood that thereare devices for 'rocking the arm 2 and ixin'g it in any desiredposition, whereby the position of the brush with relation to' thecommutator-eylinder may be adjusted in any ordinary and well-knou-'nmanner.'` Such mechanism is for this reason not shown. The brushholderproper consists of a casting 4, for'med with a wide. slot 5,:ulap1rultoreceive and guide 'the eolloetor-ln'ush (3, which latter has thegeneral outline of a' flat prislnatie plate, with its free end formed tobear at all points upon the sin-lime ol'` the c0mniuta-tor-cylinder, asusual. 'lo one end of the brush-holder is pivoted the frame 7, whichsupports the mechanism for feeding the brush forward, as it wears olT byuse. lt consists in a bar S, having` on its outer face secured a bracket0, and this frame when in the position shown in liigs. l, 2, and lcloses one end of the slot 5, und in this position a hooked end-l0,formed at the free end of bnr oo 8, eugagesthe shank of a screw il, hvwhieh it is locked. There is a square hole formed both in the bracketSi and in the plate S, the

.two holes being in alignment, and through -be seen that by themechanism .so 12o-de-A ICO folloiifer '14 bearing upon the rear end ofthe `these devices for the sake description.-

' carbon plates -With copper plates betweenl :'in any desired manner,and I do not Iherein scribed-the tension ofthe spring 15 may beadjusted' after tliebrusli 6 has been inserted into the slot 5 of thebrush-holder 4, with a brush, While the' forward end of the brush bearsupon the coinniutator-eylinder l. 1 n

All these devices forsupporting, adjusting, and feeding thecollector-brush maybe varied claim the saine, and 'I have onlyillustrated of completeness of My present improvement is altogetherconi'ined tothe construction -of the collectorbriish, which I will nowdescribe. As shown in the drawings, this brush consists of alteriiatelaininzie of metal I8 and of carbon I9, the carbon being preferably of afine and uniform grain, while the metal I prefer, without,

per. I thus `assemble alternate layers of copper and carbon and securethe same together by rivets or bolts 20, and by preference the oppositewide faces of .the brush 'are fornied of' copper.v In fact, I may use asinglercarbon plate having a. copper facing-plate 18, 'ap-l plied toboth broad faces.

of two carbon plates with a copper plate between them and a copper plateonjth'e outer face of each carbon plate, I preir'e'ir;y It will be'understood' that I niay use more than two thein, together with outercopper facing-plates. A collector-brush thus constructed with alternatelayers of carbon and metal has the ad-l vantages of carbon and copperbrushes conibined Without the disadvantages of either of them. The'goodintimate Contact produced by the Simple carbon brush is also secured bylinnn. La,

by agentle pressure; Y lio-Wever, being eonned te the sani'e, is cop- 'rThe construction, however, shown in the drawings, consisting in ycomposite brush ,wliile the freedom from danger of chipping or breakingoit which is l tween its contact-face and the brush-holder, -for thereisno'dangerof breaking, as inthe simple carbon brush. Y

In the drawings I have shown rivets 2O for securing -the alternatelamina; of carbon and i copper together, and in order to prevent t-liecracking of the carbon plates by theact of riveting these rivets fw'illpreferably be niade of seine very soft iiietal, such as lead or tin; butlharder rivets may be used without (ianger of cracicii'ig or breakingthe carbon if the .riveting is done by heating the rivets in place bythe passage of a current of electricity through the saine and thenupsetting the ends l. A eoniiniitator-brush for.'dynaino-elecitrieinachines, consisting of valternate strips or platesof carbon-and metal, 4substantially as described',

2.' A" coniinutator-brusb4 for 'dynamo-electric machines, consisting ofalternate strips or plates of copper and ca rbon, substantially asdescrieed. -A 3. A commentator-brush 'for dynamoelec tric machines,consisting of a series of alter-` nate strips or platecsof carbon andmetal, the

two subscribing witnesses.

JAMES F. MCLAUGIILIN. lVitncsses: i II. I?. REARDON, HERBERT l. KER.

